The DOCTORS study is a randomized, open label study to evaluate whether OCT-guided angioplasty would provide useful clinical information beyond that obtained by angiography, and whether this information would subsequently modify physician behavior and treatment choices. In particular, we will evaluate the impact of changes in procedural strategy resulting from the use of OCT on the value of fractional flow reserve (FFR) obtained after angioplasty and stent implantation of a lesion responsible for non-ST segment elevation acute coronary syndromes.